There are
744 mi
from Clarksville, TN to New Smyrna Beach, FL
That's the driving distance. It would take 13 hours 47 mins to go from Clarksville, Tennessee to New Smyrna Beach, Florida.
The flight distance (direct flight from Clarksville, TN to New Smyrna Beach, FL) is 638.72 mi.
744 mi = 1,197.38 kms